Ratchet device for lifting-jacks.



FRANK L. GORMLEY, OF BOSTON, MASSACHUSETTS.

RATCHET DEVICE FOR LIFTING-JACKS.

Specification of Letters Patent.

Application filed June 16, 1909.

Patented Feb. 7, 1911.

Serial No. 502,840.

To all whom it may concern:

Be it known that I, FRANK L. GoRMLnY, a citizen of the United States ofAmerica, and a resident of Boston, in the county of Sufiolk and State ofMassaolmsetts, have invented certain new and useful Improvements inRatchet Devices for Lifting-Jacks, of which the following is aspecification.

This invention relates to lifting jacks and particularly to that classof jacks which are known as ratchet screw jacks and which aremanipulated by an operating handle carrying a double ended pawl, eitherend of which is adapted to engage with a ratchet wheel on the operatingshaft.

The object of the present invention is to simplify the mechanism forretaining either end of the double-ended pawl in engagement with theratchet wheel and to provide a means for regulating the tension of saidmechanism.

The invention consists in certain novel features of construction andarrangement of parts which will be readily understood by reference tothe description of the drawings and to the claims hereinafter given.

Of the drawings: Figure 1 represents a plan of a jack embodying thefeatures of this invention. Fig. 2 represents a vertical section of thesame, the cutting plane being on line 22 on Fig. 1, and Fig. 3represents a vertical section of the same, the cutting plane being online 33 on Fig. 1.

Similar characters designate like parts throughout the several figuresof the drawings.

In the drawings, 10 represents a suitable base supporting a stationarystandard 11 over the outer periphery of which is fitted a movable sleeve12, to the upper end of which is threaded a head 13. In the upper end ofthe head 13 is mounted a plate 14:, between the upper end of which andthe inner face of the head 13 is interposed a friction disk 15 while thefriction disk 16 is inter posed between the under face of said plate andthe upper face of a beveled gear 17 splined to the reduced upper end ofa screw 18, the threaded end of which is threaded to a nut 19 mounted inthe upper end of the standard 11. The gear 17 meshes with a gear 20secured to or formed upon a revoluble shaft 21 mounted in the bearing 22on the side of the movable member 12. To the reduced end of therevoluble shaft 21 is splined or otherwise secured a ratchet wheel 23between two arms 24 of a bifurcated member 25. This bifurcated member 25is provided with an extension 26 which may be gripped by the operator tocause an oscillation of the member 25 about the shaft 21, the arms 2 1thereof being freely movable about the axis of said shaft. The member 25is provided with projecting cars 27 carrying a pin 28 on which ismounted the doubleended pawl 29, one tooth of which is adapted to engagewith the teeth of the ratchet wheel 23 to move the shaft 21 in onedirection while the other tooth is adapted to engage with said teeth toprovide a reverse movement of said shaft 21. One end of the pawl 29 isprovided with two beveled faces 30 and 31, either one of which isadapted to be engaged by a projection 32 secured to or formed upon theyielding spring member 33 secured by suitable screws to the inner faceof the member 25. Preferably the projection 32 is formed from the plate33 by a suitable bend therein.

It is obvious from an inspection of the drawings that when the upperface of the projection 32 engages with the inclined face 31 of the pawl29 the tooth farthest away from the member 33 will be retained inengagement with the teeth of the ratchet wheel 23 and the manipulationof the handle 26 will cause the shaft 21 to be revolved in the directionof the arrow on Fig. 3 of the drawings. Should a reversal of themovement of the shaft be desired the pawl 29 maybe moved into theposition indicated in dotted lines on Fig. 3 of the drawings and theunder face of the projection 32 will then come into contact with theface 30 of said pawl 29 and retain the other tooth of the pawl inengagement with the teeth of the ratchet wheel 23 so that themanipulation of the handle 26 will cause a movement of the shaft 21 in adirection opposite to that indicated by the arrow on said figure.

A lug 34 projecting from the member 25 has threaded thereto a member 35,the inner end of which engages with the yielding member 33 to regulatethe tension thereof so that the teeth of the pawl 29 may be more or lessfirmly held in engagement with the ratchet wheel 23, as desired. Thisprovides a very simple mechanism for retaining the pawl in engagementwith the ratchet wheel and allowing it to be moved about its pivot 28 tocause an engagement of either of its two ratchet-engaging teeth. Itsimplifies the construction of the operating mechanism affording a readymeans of dismantling the Various elements of the operating mechanismwhen it is desired to dismember the jack for any reason.

It is believed that the operation and many advantages of the inventionwill be thoroughly understood from the foregoing.

Having thus described my invention, I claim:

1. In combination, a spindle; a ratchet Wheel secured thereto; anoscillating handle on said spindle provided with two ears at rightangles to its operating arm; a double pawl pivotally mounted in saidears carried thereby and having two oppositely beveled faces at one end;a flat yielding member secured to said handle between said ears and anda member threaded to said lug and adapted to bear upon an intermediateportion of said flat yielding member and regulate the tension thereof.

2. In combination, a spindle; a ratchet wheel secured thereto; anoscillating handle 011 said spindle provided with two cars at rightangles to its operating arm; a double pawl pivotally mounted in saidears carried thereby and having two oppositely beveled faces at one end;a flat yielding member secured to said handle between said ears and bentat its outer end to form a projection adapted to engage with eitherbeveled face of said pawl to retain either end thereof in engagementwith said ratchet wheel; a lug on said handle; and a'memb er threaded tosaid lug and adapted to bear upon an intermediate portion of said flatyielding member and regulate the tension thereof.

Signed by me at 4 Post Office Sq., Boston, Mass, this 4th day of June,1909.

FRANK L. GORMLEY. Vitnesses VVALTER E. LOMBARD, NATHAN C. LOMBARD.

